﻿using System;
using System.Globalization;
using System.Linq;
using System.Windows;
using System.Windows.Data;

namespace LINQPad.OpenAccess.UI.Converters
{
    /// <summary>
    /// Negates a boolean value and converts it to the corresponding <see cref="Visibility"/>.
    /// </summary>
    [ValueConversion( typeof( Boolean ), typeof( Visibility ) )]
    public class NegatedBooleanToVisibilityConverter : IValueConverter
    {
        #region IValueConverter Members

        /// <summary>
        /// Converts a value.
        /// </summary>
        /// <param name="value">The value produced by the binding source.</param>
        /// <param name="targetType">The type of the binding target property.</param>
        /// <param name="parameter">The converter parameter to use.</param>
        /// <param name="culture">The culture to use in the converter.</param>
        /// <returns>
        /// A converted value. If the method returns null, the valid null value is used.
        /// </returns>
        public object Convert( object value, Type targetType, object parameter, CultureInfo culture )
        {
            if ( !( value is bool ) )
                throw new NotSupportedException( "Unsupported value !" );
            return ( ( bool ) value )
                    ? Visibility.Collapsed
                    : Visibility.Visible;
        }
        /// <summary>
        /// Converts a value.
        /// </summary>
        /// <param name="value">The value that is produced by the binding target.</param>
        /// <param name="targetType">The type to convert to.</param>
        /// <param name="parameter">The converter parameter to use.</param>
        /// <param name="culture">The culture to use in the converter.</param>
        /// <returns>
        /// A converted value. If the method returns null, the valid null value is used.
        /// </returns>
        /// <exception cref="System.NotSupportedException">Unsupported value !</exception>
        public object ConvertBack( object value, Type targetType, object parameter, CultureInfo culture )
        {
            if ( !( value is Visibility ) )
                throw new NotSupportedException( "Unsupported value !" );
            return ( ( Visibility ) value ) == Visibility.Visible
                        ? false
                        : true;
        }

        #endregion
    }
}
